Firefighters rescue Hank the dog from 20-feet deep water well in River Oaks

A black Labrador retriever named Hank is home safe after falling 20 feet into a water well in River Oaks, officials say.

The Fort Worth Fire Department assisted the River Oaks Fire Department in a "confined space rescue operation" to haul Hank from the bottom of the cistern.

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Officials said that despite low oxygen levels inside the well, Hank was alert and attentive.

According to the FWFD, a firefighter secured with a rope and oxygen descended into the well and grabbed Hank in under four minutes. They said the entire operation took about 38 minutes.

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Once above ground, FWFD said Hank was given oxygen and assessed for injuries, and they were happy to report he was healthy and unharmed.

Authorities did not explain how Hank ended up in the cistern or if he had a family.